JP2019147673A - Post-processing device - Google Patents

Abstract

To provide a post-processing device capable of discharging a large-sized sheet without sticking or buckling.SOLUTION: A post-processing device includes: a discharge port 9 through which a sheet is discharged; a discharge tray 11 on which the sheet discharged from the discharge port 9 is stacked; a movable guide 13 configured to protrude upward of the discharge tray 11 when the sheet is discharged from the discharge port 9 to guide the sheet, and is retracted from upward of the discharge tray 11 after the sheet is discharged, and having a blower port 41 at a tip in a sheet discharge direction; a blower 55 that generates an airflow from the blower port 41 toward the discharge direction; and a controller that performs control so that the movable guide 13 is protruded and the blower 55 is driven to generate the airflow.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a post-processing apparatus that performs stapling or punching on a sheet.

  In an image forming apparatus that forms an image on a sheet or a post-processing apparatus that performs stapling or punching on a sheet, the image-formed sheet or the post-processed sheet is stacked on a discharge tray. When there are a plurality of sheets, the next sheet is discharged onto the upper surface of the sheets stacked on the discharge tray. In this case, there is a problem that the sheet discharged later sticks or buckles on the previously discharged sheet, resulting in poor sheet alignment.

  As described in Patent Document 1 and Patent Document 2, there are cases where a blowing means is provided for such a problem. In Patent Document 1, air is blown to a sheet from between a discharge unit that discharges the sheet and a stacking unit (discharge tray) that stacks the sheets. In Patent Document 2, air is blown along the direction parallel to the discharge direction of the recording medium on the upper surface side of the recording medium (sheet) discharged from the discharge means.

JP 2013-136453 A JP 2013-184809 A

  However, in the air blowing means described in Patent Document 1 and Patent Document 2, when the size of the sheet is large, the air cannot be sufficiently blown up to the leading edge of the sheet, and the sticking or buckling of the sheet is ensured. It is difficult to improve.

  In view of the above circumstances, an object of the present invention is to provide a post-processing apparatus that can discharge a large-sized sheet without sticking or buckling.

  In order to solve the above-described problems, the post-processing apparatus of the present invention includes a discharge port for discharging a sheet, a discharge tray on which a sheet discharged from the discharge port is stacked, and a sheet being discharged from the discharge port. The sheet is projected above the discharge tray to guide the sheet, and after the sheet is discharged, the sheet is retracted from above the discharge tray, and a movable guide having a blower port at a leading end in the sheet discharge direction, and the discharge from the blower port. A blower that generates an airflow directed in a direction, and a control unit that causes the movable guide to project and drives the blower to generate the airflow are provided.

  In the post-processing apparatus of the present invention, the sheet is discharged from the discharge port by rotating in one direction, the discharge roller for switching back the sheet by rotating in the direction opposite to the one direction, and the switchback by the discharge roller. A processing tray on which the stacked sheets are stacked, and the control unit projects the movable guide when the sheets are switched back and drives the blower to generate the airflow. good.

  In the post-processing apparatus of the present invention, the movable guide has a duct that forms a flow path from the blower to the blower port therein, and the duct has a tapered cross section toward the blower port. It may be characterized by being.

  According to the present invention, since the air current is blown from the protruding front end of the movable guide to the upper surface of the discharge tray, the air current can be distributed to the front end of the large size sheet. Therefore, a large-sized sheet can be stacked on the discharge tray without sticking or buckling.

It is a front view which shows typically the internal structure of the post-processing apparatus which concerns on one Embodiment of this invention. It is sectional drawing which shows the structure of the discharge port vicinity of the post-processing apparatus which concerns on one Embodiment of this invention. In the post-processing apparatus which concerns on one Embodiment of this invention, it is a front view which shows typically the movable guide in a guide position and a retracted position. In the post-processing apparatus which concerns on one Embodiment of this invention, it is a side view which shows typically the drive part of a movable guide. It is a block diagram which shows a control part in the post-processing apparatus which concerns on one Embodiment of this invention.

  Hereinafter, a post-processing apparatus according to an embodiment of the present invention will be described with reference to the drawings.

  First, the overall configuration of the post-processing apparatus 1 will be described with reference to FIG. FIG. 1 is a cross-sectional view of the post-processing apparatus 1. The front side of the sheet of FIG. 1 is the front side of the post-processing apparatus 1. Fr, Rr, L, and R in each figure indicate the front side, the rear side, the left side, and the right side of the post-processing apparatus 1, respectively. For example, the post-processing apparatus 1 is disposed adjacent to the image forming apparatus and performs post-processing on a sheet on which an image is formed by the image forming apparatus.

  The post-processing apparatus 1 has a substantially rectangular parallelepiped body portion 3 and leg portions 5 that support the body portion 3. In the main body 3, a carry-in port 7 is formed on the side surface (right side surface) on the image forming apparatus side, and a discharge port 9 is formed on the side surface (left side surface) opposite to the image forming apparatus. A sheet is carried into the carry-in entrance 7 from an image forming apparatus or the like. The post-processed sheet is discharged from the discharge port 9. A discharge tray 11 on which discharged sheets are stacked is provided below the discharge port 9 so as to be movable in the vertical direction. Further, a movable guide 13 that mainly guides a small-sized sheet is provided between the discharge port 9 and the discharge tray 11 so as to protrude above the discharge tray 11 from the inside of the main body 3. Further, a conveyance path 15 that conveys the sheet along the conveyance direction from the carry-in port 7 toward the discharge port 9 is formed inside the main body 3.

  Inside the main body 3, a punching device 17 that punches sheets in order from the upstream side in the transport direction, a processing tray 19 for placing a sheet bundle, and a sheet bundle placed on the processing tray 19 are stapled. And a stapling device 21 that binds at a position along the transport path 15. Furthermore, a carry-in roller pair 23 is provided on the downstream side of the punching device 17 in the transport path 15, and a discharge roller pair 25 is provided inside the discharge port 9. Note that the post-processing apparatus 1 may be provided with a half-folding device that folds the sheet. The main body 3 is provided with a control unit 27 that controls the rotation of the carry-in roller pair 23 and the discharge roller pair 25.

  Next, the structure of the discharge roller pair 25, the processing tray 19, and the movable guide 13 will be described with reference to FIGS. FIG. 2 is a front view showing the vicinity of the discharge port of the post-processing apparatus, and FIG. 3 is a front view schematically showing the movable guide at the guide position and the retracted position.

  As shown in FIG. 2, the discharge roller pair 25 includes an upper roller 31 and a lower roller 33. The upper roller 31 is supported above the discharge port 9 by the roller holder 35 so as to be able to rotate forward and backward. The roller holder 35 is supported so as to be swingable upward. The lower roller 33 is supported below the discharge port 9 so as to be rotatable forward and backward. As the roller holder 35 swings upward, a gap is opened between the upper and lower rollers 31 and 33. The roller holder 35 swings under the control of the control unit 27.

  The processing tray 19 is disposed below the conveyance path 15 between the carry-in roller pair 23 and the discharge roller pair 25. The processing tray 19 is inclined downward from the discharge port 9 toward the inside of the main body 3 so that the rear ends of the sheets stacked on the processing tray 19 are aligned. The stapling device 21 performs a stapling process on the sheets whose rear ends are aligned. The stapling device 21 is provided so as to be movable in the width direction intersecting the paper transport direction along the lower end portion of the processing tray 19 and can select a position for stapling. A pair of side cursors 39 are supported on the processing tray 19 so as to be slidable in the width direction.

  As shown in FIG. 3, the movable guide 13 is a hollow member that has a length along the transport direction shorter than that of the discharge tray 11 and is slightly curved in an upwardly convex arc shape in a side view. A blower port 41 is formed on the front surface of the movable guide 13 in the discharge direction. The blower ports 41 are formed at predetermined intervals along the width direction. An opening 43 is formed on the surface on the rear end side in the discharging direction. Inside the movable guide 13, a duct 45 having a channel whose cross section tapers from the opening 43 toward the tip is formed.

  The movable guides 13 are disposed at both ends of the discharge port 9 in the width direction, and are retracted (see a two-dot chain line in FIG. 3) stored in the storage unit 51 provided in the main body 3, and the discharge tray 11. It is supported so as to be movable between a guide position protruding upward (see a solid line in FIG. 3). The accommodating portion 51 has a size and shape that can accommodate the movable guide 13. The gap between the movable guide 13 and the accommodating portion 51 is preferably as narrow as possible. At the guide position, the tip of the movable guide 13 protrudes slightly upstream from the central portion of the discharge tray 11. The movable guide 13 is driven by the drive unit 70 shown in FIG. 4 and moves between the retracted position and the guide position.

  The drive unit 70 will be described with reference to FIG. FIG. 4 is a side view schematically showing the drive unit.

  Rack teeth 71 are formed on the lower surface of each movable guide 13 along the length direction of the movable guide 13. The drive unit 70 is provided in the storage unit 51, a pinion gear 73 that meshes with the rack teeth 71 of the movable guide 13, a motor 75 that rotates the pinion gear 73, and a transmission mechanism that transmits the rotation of the motor 75 to the pinion gear 73. 77.

  The transmission mechanism 77 includes a reduction gear 79 that meshes with the output gear 75 a of the motor 75, a transmission shaft 83 that is connected to the reduction gear 79 via the first timing belt 81, and a transmission shaft 83 and a second timing belt 85. And a drive gear 87 to be connected. The drive gear 87 meshes with the pinion gear 73 via the idle gear 89.

  When the motor 75 is driven and the output gear 75a rotates in one direction, the pinion gear 73 rotates in one direction (counterclockwise direction in FIG. 4, see arrow) via the transmission mechanism 77, and the solid line in FIG. As shown, the movable guide 13 having the rack teeth 71 meshing with the pinion gear 73 moves from the retracted position to the guide position. On the other hand, when the output gear 75a rotates in the other direction, the pinion gear 73 rotates in the other direction (clockwise direction in FIG. 4) via the transmission mechanism 77 and is movable as shown by the two-dot chain line in FIG. The guide 13 moves from the guide position to the retracted position. The motor 75 is controlled by the control unit 27 and rotates. The motor 75 and the transmission shaft 83 are commonly used for the movable guides 13 disposed at both ends of the discharge port 9 in the width direction.

  A roller 91 is rotatably supported on the rotation shaft of the lower roller 33 of the discharge roller pair 25. When the movable guide 13 moves between the guide position and the retracted position, the lower surface of the movable guide 13 is guided along the roller 91.

  Referring to FIG. 3 again, a blower fan 55 serving as a blower that generates an airflow passing through the duct 45 toward the outlet of the storage unit 51 is provided at the back end of the storage unit 51. The blower fan 55 is controlled by the control unit 27 to generate an air flow.

  The control unit 27 will be described with reference to the block diagram of FIG. As described above, the control unit 27 controls the rotation of the carry-in roller pair 23 and the discharge roller pair 25 and the swing of the roller holder 35. Further, the control unit 27 controls driving of the blower fan 55 and rotation of the motor 75 of the driving unit 70.

  In the post-processing apparatus 1 described above, the operation of the movable guide 13 during sheet discharge will be described. In addition, in order to simplify description, description about control of the carrying-in roller pair 23, the discharge roller pair 25, and the roller holder 35 by the control part 27 is abbreviate | omitted. When the post-processing apparatus 1 is driven, the control unit 27 drives the motor 75 of the drive unit 70 to move the movable guide 13 from the retracted position to the guide position. After the movable guide 13 moves to the guide position, the control unit 27 drives the blower fan 55 to generate an air flow in the housing unit 51. The generated airflow enters the duct 45 from the housing portion 51 through the opening 43 of the movable guide 13 and is blown out from the blower port 41 as indicated by an arrow in FIG. As described above, since the tip of the movable guide 13 protrudes slightly upstream from the central portion of the discharge tray 11 at the guide position, the air flow blown from the blower port 41 causes the upper surface of the discharge tray 11 to be discharged in the discharge direction. To the downstream side.

  First, a case where the sheet is not subjected to stapling will be described. In the discharge roller pair 25, the roller holder 35 does not swing, and the upper and lower rollers 31, 33 are in contact with each other and rotate in the forward direction. After the sheet is conveyed by the carry-in roller pair 23, the sheet is conveyed to the discharge roller pair 25, and is discharged from the discharge port 9 by the rotation of the upper and lower rollers 31 and 33 in the forward direction. As shown in FIG. 3, the sheet S is guided along the movable guide 13, and is discharged in a state where it is floated from the discharge tray 11 by the air flow along the upper surface of the discharge tray 11. Immediately before the trailing edge of the sheet passes through the discharge roller pair 25, the control unit 27 drives the motor 75 of the drive unit 70 to move the movable guide 13 from the guide position to the retracted position. During this time, the airflow from the movable guide 13 is continued. After the sheet is completely discharged from the discharge port 9, it falls to the discharge tray 11 by its own weight. At this time, since the movable guide 13 is retracted from above the discharge tray 11, it does not interfere with the sheet.

  After the first sheet is discharged, the control unit 27 drives the motor 75 of the drive unit 70 to move the movable guide 13 from the retracted position to the guide position. Thereafter, the second sheet is discharged in the same manner as described above, and is stacked on the first sheet. At this time, since the airflow is blown out from the air blowing port 41 of the movable guide 13 along the upper surface of the first sheet, the second sheet is discharged in a state of being floated from the first sheet, It is stacked on the first sheet. The third and subsequent sheets are similarly stacked on the second sheet. The discharge tray 11 moves downward according to the number of sheets stacked.

  Next, a case where the sheet is stapled will be described. Even when the stapling process is performed, the control unit 27 rotates the motor 75 of the driving unit 70 to move the movable guide 13 from the retracted position to the guide position. Further, the control unit 27 drives the blower fan 55 to generate an airflow along the upper surface of the discharge tray 11 from the blower opening 41 of the movable guide 13.

  In the discharge roller pair 25, the roller holder 35 swings upward, and a gap is opened between the upper and lower rollers 31 and 33. After the first sheet is conveyed by the carry-in roller pair 23, the first sheet is conveyed along the movable guide 13 from the discharge port 9 to above the discharge tray 11 through the gap between the upper and lower rollers 31 and 33. At this time, the sheet floats from the discharge tray 11 due to the airflow blown from the air blowing port 41 of the movable guide 13. Therefore, even if the sheet hangs from the movable guide 13 to the discharge tray 11, the sheet does not buckle.

  When the roller holder 35 is swung downward at the timing when the trailing edge of the sheet passes through the carry-in roller pair 23, the sheet is sandwiched between the upper and lower rollers 31 and 33. Thereafter, when the upper and lower rollers 31 and 33 are respectively rotated in the reverse direction, the sheet is switched back and pulled into the processing tray 19. After the sheet is pulled in until the rear end comes into contact with the rear wall of the processing tray 19, the rotation of the upper and lower rollers 31 and 33 is stopped, and the roller holder 35 is swung upward.

  After the second sheet is conveyed by the pair of carry-in rollers 23, it passes through the gap between the upper and lower rollers 31, 33 and is discharged along the movable guide 13 from the discharge port 9 to above the discharge tray 11. At the timing when the trailing edge of the sheet passes the carry-in roller pair 23, the roller holder 35 is swung downward, and then the upper roller 31 is rotated in the reverse direction. Then, the sheet is switched back and pulled into the processing tray 19. After the sheet is pulled in until the rear end comes into contact with the rear wall of the processing tray 19, the rotation of the upper roller 31 is stopped and the roller holder 35 is swung upward. Thereafter, the sheet is aligned in the width direction by the pair of side cursors 39.

  By repeating this operation, a predetermined number of sheets are stacked on the processing tray 19 to form a sheet bundle. Thereafter, stapling is performed on the sheet bundle by the stapling device 21. During this time, the sheet bundle is sandwiched between the upper and lower rollers 31 and 33.

  When discharging the stapled sheet bundle, the upper and lower rollers 31 and 33 rotate in the forward direction, and the sheet bundle is discharged along the movable guide 13 to the discharge tray 11. Immediately before the rear end of the sheet bundle passes the discharge roller pair 25, the control unit 27 drives the motor 75 of the drive unit 70 to move the movable guide 13 from the guide position to the retracted position. During this time, the airflow from the movable guide 13 is continued.

  As described above, according to the present invention, when discharging a sheet to the discharge tray 11, an air flow is blown from the protruding front end of the movable guide 13 to the upper surface of the discharge tray 11. You can spread the airflow up to. Therefore, a large-sized sheet can be stacked on the discharge tray 11 without sticking or buckling. Similarly, stapled sheets can be stacked on the discharge tray 11 without sticking or buckling. Further, since the stapled sheet bundle is heavier than one sheet, the air volume of the blower fan 55 may be increased.

  Further, when the sheet to be stapled is switched back, an air flow is blown from the protruding front end of the movable guide 13 to the upper surface of the discharge tray 11. Therefore, even when a sheet hangs down from the movable guide 13 to the discharge tray 11 during switchback, the sheet can be stacked on the processing tray 19 without sticking or buckling. However, it is not always necessary to generate airflow at the time of switchback.

  Further, since the duct 45 of the movable guide 13 has a tapered cross section toward the tip, the pressure of the airflow blown out from the blower port 41 is increased, and the airflow is surely delivered to the downstream side of the discharge tray 11. Can be spread. Further, a branch channel that communicates from the opening 43 to each of the air blowing ports 41 may be formed in the duct 45. In this case, since the airflow generated by the blower fan 55 can be concentrated and sent to the blower port 41 through the branch flow path, the pressure of the airflow blown from the blower port 41 can be increased. Or you may form the flange which protrudes from the circumference | surroundings of the opening 43 of the movable guide 13 so that it may adjoin to the internal peripheral surface of the accommodating part 51. FIG. Also in this case, the airflow generated by the blower fan 55 can be efficiently sent into the duct 45.

  Alternatively, the movable guide 13 may be formed in a U shape in cross section with the lower surface opened instead of being hollow. In this case, when the air flow is blown from the blower fan 55 toward the lower surface of the upper wall of the movable guide 13, the air flow flows in the direction of the blower port 41 along the lower surface of the upper wall and is blown out from the blower port 41. Alternatively, the blower fan 55 may be directly attached to the tip of the movable guide 13.

  Furthermore, since the description of the embodiment of the present invention described above describes a preferred embodiment of the post-processing apparatus according to the present invention, there may be various technically preferable limitations. The technical scope of the present invention is not limited to these embodiments unless specifically described to limit the present invention. That is, the above-described components in the embodiment of the present invention can be appropriately replaced with existing components and the like, and various variations including combinations with other existing components are possible. The description of the embodiment of the present invention described above does not limit the contents of the invention described in the claims.

DESCRIPTION OF SYMBOLS 1 Post-processing apparatus 9 Discharge port 11 Discharge tray 13 Movable guide 19 Processing tray 27 Control part 31 Upper roller (discharge roller)
41 Blower 45 Duct 55 Blower (Blower)

Claims (3)

A discharge port through which the sheet is discharged;
A discharge tray on which sheets discharged from the discharge port are stacked;
When a sheet is discharged from the discharge port, the sheet protrudes above the discharge tray and guides the sheet. A movable guide;
A blower that generates an airflow from the blower opening toward the discharge direction;
A post-processing apparatus, comprising: a control unit that causes the movable guide to protrude and drives the blower to generate the airflow. A discharge roller that discharges the sheet from the discharge port by rotating in one direction and switches back the sheet by rotating in the direction opposite to the one direction;
A processing tray on which sheets switched back by the discharge roller are stacked,
2. The post-processing apparatus according to claim 1, wherein when the seat is switched back, the control unit causes the movable guide to protrude and drives the blower to generate the airflow.   The said movable guide has a duct which forms the flow path which goes to the said air outlet from the said air blower inside, The said duct has a taper cross section toward the said air outlet. The post-processing apparatus according to 1 or 2.

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